| Growth, physiological responses, the nature and presence of quaternary ammonium compounds (QACs) and their accumulation in carrot (Daucus carota L.var. sativus) cv. Oranza, onion (Allium cepa L.) cv. Prince, and tomato (Lycopersicon esculentum Mill.) cv. Sunstart, in response to varying degrees of water stress were studied. Twenty-one day-old carrot, onion, and tomato seedlings were subjected to a progressive water deficit by withholding water.; Glycinebetaine (carrots and onions) and trigonelline (tomato) were applied to precondition the seeds by a 24h seed-soak at various concentrations. Seeds were then dried and sown into pots containing a professionally mixed medium of peat and vermiculite. Twenty-one day-old carrot, onion, and tomato seedlings were then subjected to a severe water deficit, gradually, by withholding water.; Both, GB and trigonelline protected elongation growth, probably through maintenance of cell division and extension and stabilizing membranes in plants under water deficit, perhaps by expression of specific genes, as the seeds were preconditioned. (Abstract shortened by UMI.)... |
